Experiments and CFD of a high-speed deep-V planing hull––Part I: Calm water

Abstract

Comparisons of experimental and simulation results for a high-speed deep-V planing hull are presented. The goal of this investigation is to improve the physical understanding of, as well as assess the experimental and CFD capability for, deep-V planing hulls operating in calm water and slamming when running in head waves (both regular and irregular). This paper consists of two parts, which deal with the calm water and slamming in waves, respectively. In Part I, simulations for trim, sinkage, and resistance in calm water are compared with experiments on a deep-V planing hull at the U.S. Naval Academy and at Naval Surface Warfare Center – Carderock. Two model scales of the same geometry were tested in calm water at a range of speeds. Comparisons between the scale models, between the same model tested at both facilities, and comparisons between simulation and experiment are discussed. The results showed the importance of precise geometric (particularly for the transom) and hydrostatic information for simulation predictions. The comparisons also showed the need for greater resolution of the spray root to achieve the best predictions involving trim (and wetted lengths). Overall, there was general agreement between the facilities, even for the calm water trim. The CFDShip-Iowa and STAR-CCM+ calm water validation effort was conducted with the larger model results from NSWCCD. Validation was not achieved for resistance; however, Fn average error was less than 4%DR. In sinkage, both codes were validated at the highest three speeds, but not at the lowest speeds (Fn average error was less than 3%DR). For trim and wetted keel, validation was not achieved, although the validation uncertainty values were small (Fn average error was less than 4%DR). Both codes under-predicted the calm water trim and the wetted keel length was under-predicted for all but the lowest speed (Fn average error less than 1). The overall results provide an assessment of the state of the art for both experiments and CFD for high-speed deep-V planing hull resistance, sinkage, and trim. The experimental and simulation results for hull slamming in waves (both regular and irregular) are presented in Part II of this paper.